Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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APPARATUS AND METHOD FOR PRODUCING A SEALED SINGLE-
DOSE BREAK-OPEN PACKAGE
Description
Technical Field
The present invention relates to an apparatus and to a production method
for producing a sealed single-dose break-open package.
Background art
The patent application W02008038074A2 describes a sealed single-dose break-
open package; the sealed package comprises a sheet of semi-rigid plastic
material
to and a sheet
of flexible plastic material which is superposed on and sealed to the
sheet of semi-rigid plastic material to form a sealed pocket that contains a
dose of
a fluid product. The sheet of semi-rigid plastic material has in the central
part a
weakened zone for guiding controlled breakage of the sheet of semi-rigid
plastic
material in such a way as to cause the formation of an outlet opening for the
product through the sheet of semi-rigid plastic material itself In other
words, to
open the sealed package a user must grab the sealed package itself with the
fingers
of one hand and -V"-bend the sealed package until the sheet of semi-rigid
plastic
material breaks at the weakened zone. The weakened zone comprises an inner
incision that is made through an inner surface (that is, facing the pocket) of
the
sheet of semi-rigid plastic material and an outer incision that is made
through an
outer surface of the sheet of semi-rigid plastic material and aligned with the
inner
incision.
In patent application W02008038074A2, the incisions vary in depth in order to
break the sheet of semi-rigid plastic material progressively during the "V"-
bending of the sealed package. However, making incisions that vary in depth is
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relatively complicated since it requires a very high precision of movement of
the
blades of the incision unit; amongst others, the precision of movement of the
blades of the incision unit tends to decrease with the increase of the
operating
speed and as a result, to obtain a very high precision of movement of the
blades of
the incision unit it is not possible to reach particularly high operating
speeds.
Moreover, the sealed single-dose package described in patent application
W02008038074A2 does not allow to apply (spread) the product contained inside
the package itself in a precise and intuitive manner on a surface and
therefore that
package is not suitable to contain spreadable products (that is, to be spread
on a
surface).
To make the package, patent application W02008038074A2 describes the use of
an apparatus including a reel for feeding a strip of semi-rigid material and a
reel
for feeding a strip of flexible material, an incision unit and a package
forming
station including a device for feeding the fluid product and a sealing device.
The
incision unit has two parallel, facing plates, movable towards each other to
grip
the strip of semi-rigid material, that support some blades. Each plate is
pushed
towards the other respectively by a linear actuator in order to hold the strip
of
semi-rigid material and make an incision on each side of the same.
According to an alternative method described in patent application
W02009040629A2, a "V"-shaped incision that varies in depth is made on each
side of the strip of semi-rigid plastic material, with a sharper blade on the
side of
the strip intended for the outer part of the package. The blades are pushed
one
against the other in order to hold the strip of semi-rigid material and make
the
incisions on the same. Even through this method, moving the blades turns out
to
be difficult and it is not possible to control the depth of the incision.
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Disclosure of the Invention
The object of the present invention is to provide an apparatus and a method
for
producing a sealed single-dose break-open package that are free from the above
mentioned disadvantages.
According to the present invention, an apparatus and a method for producing a
sealed single-dose break-open package are provided in accordance with the
accompanying claims.
Brief Description of the Drawings
The invention will be now described with reference to the accompanying
drawings that show some non-limiting embodiments of the invention itself,
wherein:
= figure 1 illustrates a topside view in perspective of a sealed single-
dose
break-open package produced in accordance with the present invention
and in a flat configuration;
= figure 2 illustrates an underside view in perspective of the sealed package
of figure 1 in a flat configuration;
= figure 3 is a bottom-up view in perspective of the sealed package of
figure
1 in a -V"-shaped configuration;
= figure 4 is a schematic view in cross-section and at a weakened zone of a
semi-rigid sheet of the sealed package of figure 1;
= figure 5 is a bottom-up view of the package of figure 1;
= figures 6-9 are bottom-up views of variations of figure 1 package; and
= figure 10 is a schematic view in cross-section that illustrates the
creation of
a weakened zone of a semi-rigid sheet of figure 1 sealed package;
= figure 11 is a schematic view in cross-section that illustrates the creation
of
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a weakened zone of a semi-rigid sheet of figure 1 sealed package in an
alternative embodiment;
= figure 12 illustrates an apparatus for the production of a sealed single-
dose
break-open package in a embodiment of the present invention;
= figure 13
illustrates the incision unit and the sealing and filling unit of the
apparatus of figure 12;
= figure 14 illustrates an incision unit of the apparatus of figure 12;
= figure 15 illustrates a detail of the incision unit of the apparatus of
figure
12.
Detailed Description of Preferred Embodiment of the Invention
Number 1 in figures 1 and 2 indicates as a whole a sealed single-dose break-
open
package. The sealed single-dose package 1 comprises a rectangular sheet 2 of
semi-rigid plastic material and a rectangular sheet 3 of flexible plastic
material
superposed on and sealed to sheet 2 of semi-rigid plastic material to form
(between sheets 2 and 3) a sealed pocket 4 containing a dose of a fluid
product 5.
The sheet 2 of semi-rigid plastic material may have regular or irregular shape
and
sheet 3 of flexible plastic material may have regular or irregular shape
symmetric
to the semi-rigid plastic material.
The sheet 2 of semi-rigid plastic material has a weakened zone 6 in the
central
part for guiding controlled breakage of the sheet 2 of semi-rigid plastic
material in
such a way as to cause the formation of an outlet opening for the product 5
through the sheet 2 of semi-rigid plastic material. In other words, to open
the
sealed single-dose package 1, a user has to grip the sealed single-dose
package 1
with the fingers of one hand and "V"-bend (as shown in figure 3) the sealed
single-dose package 1 until the sheet 2 of semi-rigid plastic material breaks
at the
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weakened zone 6. By breaking the sheet 2 of semi-rigid plastic material at the
weakened zone 6, the product 5 can flow smoothly and hygienically out of the
sealed single-dose package 1.
According to figure 4, the weakened zone 6 comprises one inner incision 7 (not
passing through, i.e. it does not go completely through the sheet 2 of semi-
rigid
plastic material) which is made through an inner surface 8 (that is, oriented
towards pocket 4 or facing pocket 4) of the sheet 2 of semi-rigid plastic
material
and a outer incision 9 (not passing through, i.e. it does not go completely
through
the sheet 2 of semi-rigid plastic material) that is made through an outer
surface 10
(that is, opposite to pocket 4) of the sheet 2 of semi-rigid plastic material.
The two
incisions 7 and 9 are identical (that is, shape and dimensions of the inner
incision
7 are equal to the shape and dimensions of the outer incision 9), aligned and
superposed (that is, the two incisions 7 and 9 are placed exactly in the same
position on the opposite surfaces 8 and 10 of the sheet 2 of semi-rigid
plastic
material). The two incisions 7 and 9 do not touch, that is, a residual portion
of the
sheet 2 of semi-rigid plastic material interposes itself between the two
incisions 7
and 9, to preserve the integrity of sealed pocket 4. Moreover, the sheet 2 of
semi-
rigid plastic material and the sheet 3 of flexible plastic material in this
example of
embodiment are made in such a way that incisions 7 and 9 determine the
required
breakage of the sheet 2 of semi-rigid plastic material when exposed to the
forces
generated by the "V"-bending (shown in figure 3).
According to the example of embodiment illustrated in figure 3, the sheet 2 of
semi-rigid plastic material is a laminate and includes an outer supporting
layer 11
(that is, on the side opposite to pocket 4 in the area of the outer surface
10) and an
inner supporting layer 12 (that is, on the side of pocket 4 in the area of the
inner
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surface 8). An insulating or barrier layer 13 is provided between the two
supporting layer 11 and 12 to ensure impermeability to air and/or light; in
other
words, the barrier layer 13 is enclosed by the two supporting layers 11 and 12
and
separates the supporting layers 11 and 12 itself from one another. The
supporting
layer 12 is covered by a heat-sealable layer 14 which is placed internally
(that is,
on the same side of pocket 4 and in contact with sheet 3 of flexible plastic
material to allow the heat-sealing to the sheet 3 of flexible plastic material
itself).
According to some embodiments shown in the attached figures, the two
supporting layers 11 and 12 may have the same thickness (i.e. are specular or
to twins); however, according to other embodiments, the two supporting
layers 11
and 12 may have different thicknesses, i.e. the thickness of supporting layer
11 is
different from thickness of supporting layer 12.
As non-limiting example, the sheet 2 of semi-rigid plastic material may be
composed of: a supporting layer 11 of white polystyrene (PS) with a thickness
of
i 5 200 micron ( 10%), a barrier layer 13 of -Evoh" or dialuminium with a
thickness
of 10 micron ( 10%), a supporting layer 12 of white polystyrene (PS) with a
thickness of 200 micron ( 10%), and a heat-sealable layer 14 of polyethylene
(PE) with a thickness of 50 micron ( 10%). Alternatively, supporting layers
11
and 12 may be composed of polylactic acid (PLA) preferably biaxially oriented,
20 and/or the heat-sealable layer 14 may be composed of polypropylene (PP).
Polylactic acid (PLA) is generally heat-sealable, therefore when supporting
layers
11 and 12 are made of polylactic acid (PLA), heat-sealable layer 14 may be
absent
since the sheet 3 of flexible plastic material may be heat-sealed directly to
supporting layer 12 of polylactic acid (PLA). Moreover, when supporting layers
25 11 and 12 are made of polylactic acid (PLA) or polypropylene (PP), it is
possible
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to reduce the thickness of the supporting layers 11 and 12 itself since
polylactic
acid (PLA) and polypropylene (PP) allow to obtain sufficiently rigid
supporting
layers 11 and 12 even with a small thickness. As example, if supporting layers
11
and 12 are made of polystyrene (PS), the overall thickness of supporting
layers 11
and 12 has to be higher than 350-380 micron, while if supporting layers 11 and
12
are made of polylactic acid (PLA) or polypropylene (PP) the overall thickness
of
supporting layers 11 and 12 may reach even 200 micron.
Each incision 7 or 9 has on the surface (i.e. at the surface of the
corresponding
supporting layer 11 or 12) a width W that may vary according to the plastic
material used to make the supporting layers 11 and 12: with white polystyrene
(PS) the width W of each incision 7 or 9 may range between 0,5 e 1,5 mm while
with biaxially oriented polylactic acid (PLA) or with polypropylene (PP) the
width W of each incision 7 or 9 may range between 2 and 4 mm. As a result, the
width W of each incision 7 or 9 when using biaxially oriented polylactic acid
(PLA) or polypropylene (PP) is higher than the width W of each incision 7 or 9
when using polystyrene (PS). These differences are due to the fact that
biaxially
oriented polylactic acid (PLA) and polypropylene (PP) become fragile (i.e.
easily
breakable) when crushed (deformed by compression) as occurs by making
incisions 7 and 9 and as a result, it is more convenient to have relatively
wide
incisions 7 and 9 to obtain in supporting layers 11 and 12 residual parts
(i.e. what
remains of supporting layers 11 and 12 in the area of incision 7 and 9) with a
high
fragility that helps the breakage of package 1 when it is "V"-bended (as shown
in
figure 3). According to another embodiment not shown, in the sheet 2 of semi-
rigid plastic material, supporting layer 12 is absent (i.e. the barrier layer
13 is
directly in contact with heat-sealable layer 14) and supporting layer 11 has a
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double thickness (i.e. supporting layer 12 is -embedded" in supporting layer
11).
The outer incision 9 is made through the outer surface 10 of the sheet 2 of
semi-
rigid plastic material and can be made by deforming locally the sheet 2 of
semi-
rigid plastic material and in particular the supporting layer 11 of the sheet
2 of
semi-rigid plastic material; the outer incision 9 ends before the barrier
layer 13
and therefore it does not affect the barrier layer 13 itself.
The inner incision 7 is made in the inner surface 8 of the sheet 2 of semi-
rigid
plastic material and can be executed by deforming locally the sheet 2 of semi-
rigid plastic material and in particular the supporting layer 12 of the sheet
2 of
semi-rigid plastic material; the inner incision 7 ends before the barrier
layer 13
and therefore it does not affect the barrier layer 13 itself
In the area of the inner incision 7 the heat-sealable layer 14 can be deformed
or
torn (partially or completely); in any case, at the inner incision 7 there is
no
sealing of any kind between the sheet 2 of semi-rigid plastic material and the
sheet
1 5 3 of
flexible plastic material and therefore the possible local damage of the heat-
sealable layer 14 does not have any consequence.
In a preferred embodiment, the incision 7 is made only on the inner surface 8
of
the sheet 2 of semi-rigid plastic material by deforming locally the sheet 2 of
semi-
rigid plastic material and in particular the supporting layer 12 of the sheet
2 of
semi-rigid plastic material; the inner incision 7 ends before the barrier
layer 13
and therefore it does not affect the barrier layer 13 itself (figure 11).
In some embodiments, the barrier layer 13 may be located between the two
supporting layers 11 and 12 to build a barrier for the product inside the
sealed
pocket 4. In some embodiments, the incisions 7 and 9 may not affect the
barrier
layer 13. In some embodiments, the barrier layer 13 may be thick and solid
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enough to allow a partial penetration of incisions 7 and 9 provided that the
barrier
layer 13 is designed to maintain its barrier function. In some embodiments,
the
integrity of barrier layer 13 of the sheet 2 of semi-rigid plastic material
secures the
barrier function and therefore the tightness for the content of the sealed
pocket 4
even in the area of the incisions 7 and 9 and therefore the sealed pocket 4 is
suitable to contain also perishable products and/or with controlled bacterial
load
like food, medicines or cosmetics. During the opening by breakage of the
sealed
single-dose package 1 by "V"-bending the sealed single-dose package 1 (as
shown in figure 3), it is necessary to break at the weakened area 6 all the
supporting layers 11 and 12, barrier layer 13 and heat-sealable layer 14 of
the
sheet 2 of semi-rigid plastic material.
In some embodiments, inner incision 7 and outer incision 9 may have an
essentially constant depth lengthwise (net of the inevitable construction
tolerances).
As shown in figure 5, each incision 7 and 9 (the two incisions 7 and 9 are
identical
to and superposed on each other and therefore not distinguishable in figure 5)
develops along a single line with broken shape (i.e. a single zig-zag line),
that is a
line composed of an ordered set of consecutive oriented segments (i.e. such
that
the second end of a segment matches with the first end of the following
segment)
and not adjacent (i.e. such that a segment and the following segment do not
belong to the same straight line). Moreover, each incision 7 and 9 develops
along
a single line with broken shape (i.e. a single zig-zag line) that is open
(i.e. the first
end and the last end do not match) and not intertwined (i.e. the sides of the
line
have no intersection point). According to some embodiments, the segments of
the
single line with broken shape (i.e. a zig-zag single line) along which
incisions 7
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and 9 develop are essentially parallel or essentially perpendicular and
therefore a
segment forms always an essentially right angle with the next segment.
Each incision 7 and 9 has a -U"-shaped central part 15 and two lateral parts
16
that are placed on the opposite sides of the central part 15 and connected to
the
central part 15 itself. The two lateral parts 16 are constituted of two
respective
straight line segments that have identical dimension and are aligned with each
other (i.e. one lies on the extension of the other). The central part is
constituted of
a main segment 17 that is essentially parallel to and offset from (i.e. not
aligned)
the two lateral parts 16 and of two joining segments 18 that are essentially
parallel
to and offset from each other (i.e. not aligned), are essentially
perpendicular to the
main segment 17 and are essentially perpendicular to the two lateral parts 16;
each
joining segment 18 connects a lateral part 16 to one end of the main segment
17.
On the whole, each incision 7 and 9 has a square "SY shape (i.e. constituted
only
of segments essentially parallel or essentially perpendicular to each other).
As better shown in the attached figures, the weakened zone 6 does not affect
the
whole width of the sheet 2 of semi-rigid plastic material, but affects only a
central
portion of the sheet 2 of semi-rigid plastic material leaving intact (i.e.
without the
weakened zone 6) two lateral portions of the sheet 2 of semi-rigid plastic
material
symmetrically placed on opposite sides of the weakened zone 6 itself.
According to a possible embodiment, the weakened zone 6 (i.e. the two
superposed incisions 7 and 9) increases as the density of the product 5
contained
in the pocket 4 of the sealed single-dose package 1 increases, that is, the
weakened zone 6 (i.e. the two superposed incisions 7 and 9) decreases as the
density of the product 5 contained in the pocket 4 of the sealed single-dose
package 1 decreases. As a result, the embodiment shown in figure 5 can be
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suitable to products with a higher density such as creams or granular products
while the embodiment shown in figure 6 can be suitable to products with a
lower
density like liquids.
According to different embodiments shown in figures 5-9, the main segment 17
can be linear, angled (broken) or curved. Likewise, also lateral parts 16 or
joining
segments 18 can be linear, angled (broken) or curved.
According to a possible embodiment shown in figure 10, the incisions 7 and 9
are
made by means of plastic deformation of the material using corresponding
incision tools 19, each of them having a tip that is not sharp, that is to
say, that has
a round shape (namely a rounded tip) for deforming rather than cutting the
supporting layers 11 and 12 of the sheet 2 of semi-rigid plastic material.
According to a preferred embodiment shown in figure 11, only one incision 7 is
made on the inner surface 8 of the sheet 2 of semi-rigid plastic material by
deforming locally the sheet 2 of semi-rigid plastic material and in particular
the
supporting layer 12 of the sheet 2 of semi-rigid plastic material; by means of
an
incision tool 19 having a tip that is not sharp, that is to say, that has a
round shape
(namely a rounded tip). In particular, the tip may have different degrees of
sharpness and may have any shape according to the product contained in the
package.
According to the example of embodiment illustrated in the attached figures,
the
sealed single-dose package 1 has a rectangular shape; obviously due to
aesthetic
reasons the sealed single-dose package 1 may be shaped differently: rounded,
elliptic, "bottle"-shaped, rhomboidal, pentagonal, hexagonal, triangular,
squared,
"bone"-shaped.
The sealed single-dose package 1 described above has numerous advantages.
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Firstly, the sealed single-dose package 1 described above is easier and
cheaper to
produce than a similar known package 1 (for example of the type described in
patent application W02008038074A2), since the incisions 7 and 9 have a
constant
depth and therefore are easier to be made even with high operating speed.
.. Moreover, the package 1 described above allows to dose in a simple and
efficient
way all kind of fluid (liquid or creamy), powdered or granular products and it
is
particularly suitable for spreading the product 5 on a surface thanks to the
area of
the sheet 2 of semi-rigid plastic material enclosed by the central part 15 of
the
incisions 7 ad 9 that can be separated (moved) from the rest of sheet 2 of
semi-
to .. rigid plastic material becoming a spatula useful to spread the product 5
itself. In
other words, the central portion on the main segment 17, between joining
segments 18 is designed to extend when package 1 is V-bended, in a trajectory
beyond the adjacent structures of the sheet 2 of semi-rigid plastic material
to work
as a scoop for spreading the product that comes out from the opening (as shown
in
is figure 3).
In figure 12, 20 indicates an apparatus for the production of a sealed single-
dose
break-open package 1 in a embodiment of the present invention.
The apparatus 20 includes a first feeding unit 21 of a first strip of semi-
rigid
plastic material, a second feeding unit 22 of a second strip of flexible
plastic
20 .. material, an incision unit 23 to make a deformation in the strip of semi-
rigid
plastic material and a sealing and filling unit 24 for sealing at least one
portion of
the strip of semi-rigid material to a corresponding portion of the strip of
flexible
material to create pocket 4 and for filling pocket 4.
In the illustrated embodiment, the apparatus 20 includes furthermore a
printing
25 unit 25 placed between the first feeding unit 21 of the first strip of
semi-rigid
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plastic material and the incision unit 23.
The first feeding unit 21 comprises a reel 211 from which a strip of semi-
rigid
plastic material is unwound. The reel 211 is preferably driven by a brushless
motor. The strip of plastic material has a thickness preferably ranging
between
200 micron and 450 micron.
The strip of semi-rigid plastic material goes to the printing unit 25 that
includes at
least a thermal transfer printer for printing, on the side of the strip that
will form
the outer surface of the package, a bar code, a batch indication, etc.... The
printing
unit 25 includes advantageously a number of printers 251, 252, 253 installed
in-
line.
After the printing unit 25, the strip of semi-rigid plastic material moves to
the
incision unit 23, where, according to the invention, occurs a deformation or
shaping of the side of the strip that will form the inner surface of the semi-
rigid
sheet, on which there is the heat-sealing layer.
According to the invention, as shown in figures 13, 14, the incision unit 23
includes a first plate 231 and a second pate 232 opposed to the first plate
231,
wherein the second plate 232 includes at least one incision tool 19, wherein
the
incision tool 19 is movable from a first position far from the first plate 231
to a
contact position with the first plate 231 to obtain a deformation in the strip
of
semi-rigid material placed between the first plate 231 and the second plate
232. In
particular, the incision tool 19 has a tip with different degrees of sharpness
and
may have any shape.
The surface of the first plate 231 and/or the second plate 232 is preferably
ground.
The first plate 231 represents a supporting surface for the strip to be
deformed.
As shown in detail in figure 15, the second plate 232 has at least one
micrometer
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measuring tool 191 placed on the opposite side from the first plate 231, which
adjusts the range of the incision tool 19. The tool 191 can be manual or
motorized.
Preferably, the range of incision tool 19 is adjusted in relation to the
second plate
232, and the second plate 232 is movable in relation to the first plate 231,
which is
fixed.
By means of a linear actuator or a motor, the second supporting plate 232 of
the
incision tool 19 is moved towards the first plate 231 so that one end of the
incision
tool 19 moves according to the preset distance towards the first supporting
plate
231 to create the deformation in the strip of semi-rigid material. In this way
the
to deformation or shaping is made with constant depth.
The end of the incision tool 19 has advantageously the shape of the incision
that
has to be made in the sheet of semi-rigid material.
Preferably, the second plate 232 has a number of incision tools 19 positioned
in
line, each one joined with a corresponding micrometer measuring tool 191,
manual or motorized.
The shaping is made advantageously only on the side of the strip that will
become
the inner surface 8 of the semi-rigid sheet 2.
In this way it is possible to control exactly the range of the incision tool
and
therefore the deformation depth, so that the semi-rigid sheet is not damaged
by
cutting. In particular, if this has an inner barrier layer, making the
incision by
means of the apparatus according to the present invention allows to control
that
the barrier does not get damaged.
In fact, it is no longer a matter of controlling a blade during the incision
to vary
the cutting depth along the strip, but of simply adjusting the range of the
incision
tool 19 so that this creates a deformation with constant depth and with a
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predetermined shape in the inner surface 8 of the semi-rigid sheet 2.
In the embodiment shown in figures 12, 13 and 14, the strip of semi-rigid
material
fits between the first plate 231 and the second plate 232 with an essentially
vertical bottom-up direction.
During shaping, the strip stops and leans against the first plate 231.
To perform this intermittent operation in an apparatus on continuous cycle,
the
apparatus 20 includes advantageously a blocking device 26 which determines
stop
and recovery in relation to the continuous cycle. Preferably, the blocking
device
26 allows to change the position of the deformation from the axis of the bag.
In
to the illustrated embodiment, the blocking device 26 comprises a pair
of blocking
plates 261, 262, one movable and the other fixed, placed upstream of the
incision
unit 23, in particular below the first plate 231 and the second plate 232 for
the
shaping, a pair of rubber rollers 263, 264 placed downstream of the incision
unit
23, in particular above the first plate 231 and the second plate 232, and an
active
dancer roller 265 pneumatically or electronically controlled. According to the
dimensions set by the user in the software of the apparatus, the dancer roller
265
has a double function, that is, it allows to determine the length of the bag
and the
position of the incision from the axis of the bag and to perform a mechanical
stop
without interrupting the continuous cycle of the apparatus.
After the shaping, the strip of semi-rigid material moves to the sealing and
filling
unit 24, where it is joined to the strip of flexible material coming from a
reel 221,
preferably driven by a brushless motor, of the second feeding unit 22. The
strip of
flexible material has a thickness preferably ranging between 62 micron and 100
micron.
The sealing and filling unit 24 includes a vertical sealing device 241, a
filling
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device 246 and an horizontal sealing device 247.
In the sealing and filling unit 24, the bag or the bags is/are heat-sealed,
preferably
by means of compressed air. Compared to the known devices that use springs,
the
use of compressed air allows to perform a constant sealing and to reduce
maintenance work.
The vertical sealing device 241 has a first pair of rollers including a first
rubber
roller 242 and a second warm roller 243 both equipped with grooves and a
second
pair of cold rollers 244, 245, for riveting the sealing made by the previous
pair of
rollers 242, 243, also equipped with grooves and placed below the first pair
of
.. rollers 242, 243 in vertical direction.
The horizontal sealing device 247 has a single rotary sealer, consisting of a
pair of
rollers including a first rubber roller 248 and a second warm roller 249. The
horizontal sealing device 246 closes the filled packages and at the same time,
during the rotation, it constitutes the closed base of the packages that have
still to
be filled.
In sequence, firstly the vertical seals of the package are made, than the
package is
filled, than it is closed, creating with the same movement the base for the
following package.
The apparatus 20 includes a cutting unit placed after the sealing and filling
unit
24, wherein each package is separated from the material exceeding from sealing
(scrap). The single packages are then positioned on a belt 27, that conveys
them to
the following step of production.
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